Ralph R. Teetor inventor of cruise control

Ralph R. Teetor is most well known as the inventor of cruise control and president of Perfect Circle Corporation in Hagerstown. Throughout his career, he displayed an astonishing competence with machinery and confidence with people and places even though he had been blind from the age of five. Teetor developed unusual coping mechanisms and lived his life as if he could see. Many who met him never realized he was blind.

His interest in automobiles developed early on. When he was 12 years old, Teetor and his second cousin Dan, built an automobile using an engine from the Teetor owned Light Inspection Car Company, during the summer of 1902. Mechanical engineering became his career choice and graduated from University of Pennsylvania in 1912 with a degree in this field.

In 1918, while working on a contract for the Navy at the New York Shipbuilding Corporation in Camden, New Jersey, Teetor developed a process to dynamically balance steam turbine rotors. He succeeded where many other engineers had failed. The new process was used through World War II.

In May of 1924 Teetor invented and patented a fluid-actuated automatic gear shift. The Bendix Company bought the patent and produced an automatic gearshift for Hudson. After World War II, popularity of the automatic transmission grew dramatically. For the next 40 years, most of the automatic transmissions on automobiles were based on the principles of his invention.

In 1936, Teetor was inspired to invent cruise control while riding with his patent lawyer one day. The lawyer would slow down while talking and speed up while listening. The rocking motion so annoyed Teetor that he was determined to invent a speed control device. He filed for the first patent on his device in the spring of 1945. Obstacles developed in production and delayed the debut of cruise control until 1958 on the Chrysler Imperial, New Yorker and Windsor models. Teetor’s persistence paid off again in the commercialization of a device that is now standard equipment on many automobiles.

In 1946, Teetor became president of Perfect Circle Corporation, where he had worked in various engineering capacities for the previous 32 years.

The next time you’re driving your car you can thank Ralph Teetor for inventing cruise control.